# Guide to Stoich

### Sarai Alonso

## First, what is it?

## Parts to this guide

- Reaction we are working with along with the type of reaction it is, the balanced equation, IUPAC names, and molar masses
- Mole to mole conversions
- Mass to mass conversions
- Limiting and excess reactants
- Theoretical yield
- Percent yield
- Real world aplication

## 1.) Our Reaction

This is a synthesis reaction, you can tell because a metal oxide and CO2

come together to form a metal carbonate. carbonate. In this case the metal carbonate CO3.

__ Balanced Equation__: In this case the equation does not need any coefficients (Number in front of an element or compound that is distributed) because it is already balanced meaning there is the same amount of each element on both the reactant and product side

CaO+CO2a Ca(CO3) (aq)

Calcium Carbonate and Carbon dioxide yield Calcium Carbonate

** Molar Mass: **To find molar mas, take the atomic number of the specific element from the periodic table and if there is a subscript with the element multiply the atomic mass by the subscript. If there is a compound add the individual element masses together.

CaO-56.077

CO2- 44.009

CO3- 108.005

## 2.) Mole to Mole Conversion

To do a mole to mole conversion you will have to use the train track method. Start the with the given amount of reactants and set it up so that you have moles of that same product on the bottom and moles of the product on top. To find out how many moles to calculate with, use the coefficients. Multiply the top numbers and multiply the bottom numbers then divide the top product by the bottom to get your result.

## 3.) Mass to Mass

To begin take your given amount and then take the molar mass of that element or compound and set it up, again in the train track method, to equal one mole. Set up the moles of your reactant to the moles of your product and use coefficients to know how many moles of each to calculate with. use the molar mass of the product to have one mole then, multiply the top and bottom separately and divide the product of the top by the product of the bottom

## 4.) Limiting and Excess Reactants

To find the limiting and excess reactants we will again be using the train track method. We want to convert the given masses of the reactants to moles of the product to see which one makes less product. The one that makes less is your limiting reactant.

## 5.) Theoretical Yield

Begin with your limiting reactants and set the train track so that you have the moles of your reactants with moles of your product. After that convert your moles of your product to grams using the molar mass of your product. multiply the top and multiply the bottom, then divide the top by the bottom and you will get theoretical yield

## 6.) Percent Yield

To calculate the percent yield you divide the actual yield by the theoretical yield and multiply by 100.